“Why do we even need sex scenes?” is a common enough question.
I know, some of you may feel that the actual issue is why there aren't MORE of them.
The thing is, I don’t think I’ve ever heard anyone ask, “Why do we need fight scenes?”
Yet they are quite similar to love scenes.
Two (or more) people enter a fight scene. During the fight, they will test their mental strength, their skills, exchange banter, perhaps trash-talk, and eventually get pretty up close and personal.
Very much like a sex scene.
The major difference is that when a fight ends, there is a winner and a loser.
I love the Orphan X books, I’ve read them all. The hero, Evan, is a vigilante, an assassin turned justice fighter. Towards the end of book 1, there is an elaborate fight scene that is extremely long (twelve pages long!) where, at no point, there is the slightest doubt that our hero will emerge triumphant. We don't read it wondering about the outcome just like we don’t read romance doubting the Happily Ever After.
What makes this fight redundant is that, though Evan leaves it injured, essentially nothing momentous happens to him - he hasn't gone through a big emotional upheaval or discovered new truths about himself. The plot hasn’t moved forward. This specific fight could be as short as a gunshot. It would have made no difference.
But sex scenes happen for a reason–to leave a trace on the hero or heroine’s soul. Even if the characters tell themselves, and each other, that this means nothing, that’s never true. The reader knows it even if they don’t.
Here, too, the details matter. Where they touch, the glances exchanged, the sighs and caresses–because the specifics, same as in a fight scene, create the intimacy.
Unlike a fight scene, there is no need for a definite victor.
And, this may be the most important reason to have sex scenes - they're FUN to read.
I always include steamy scenes in my books, I believe they add and enhance my stories.